Wireless signaling system.



(No Modai.)

WIRELESS SIGNALING SYSTEM.

(Application filed Sept 22, 1902.)

2 Sheets-Sheet l.

III! I r J0 g6 42 Twil 0 9 I 6] 8 Q7 44 v HIII liii ELIML T J\ 27 0'3MTJCGJSJJ E No. 7II,266. Patented on. l4, I902.

H. SHDEMAKEB.

WIRELESS SIGNALING SYSTEM.

(Application filed Sept. 22, 1902.)

(In Indol.) 2 Sheet8$heei 2.

76:23.4 /a A K7Z7-LL42%;

UNTTED STATES PATENT OFFICE.

HARRY SHOEMAKER, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THECONSOLIDATED \VIRELESS TELEGRAPH AND TELEPHONE COMPANY AND MARIE V.GEI-IRING, OF PHILADELPHIA, PENNSYLVANIA.

WIRELESS SIGN ALING SYSTEM.

SPECIFICATION forming part of Letters Patent 0. 71 1,266, dated October14, 1902.

Original application filed September 13, 1902, Serial No.123,23'7.Divided and this application filed September 22, 1902- SerialNo.124,295. (No model.)

To (all 1071,0111 it may concern.-

Be it known that I, HARRY SHOEMAKER, a citizen of the United States,residing at Philadelphia, in the county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inWireless Signaling Systems, of which the following is a specification.

My invention relates to signaling systems in which eloctroradiant energyis employed to represent the message or signal, such energy beingtransmitted through the natural media and causing manifestations at thereceiving-station, which are translated into a message or signal.

My invention consists of asystem for transmitting intelligence whereby aplurality of messages may be simultaneously or independently transmittedfrom or received at a single station.

My invention consists of a system where an element of a signal isrepresented by a train or trains of waves of electroradiant energy, suchtrains succeeding each other at prede" termiued and uniform rate.

My invention comprises a system where there are emitted simultaneouslyor independently from a single radiating-conductor a plurality of seriesof trains of waves of electroradiant energy, the trains of the severalseries succeeding each otherat different uniform rates and wherein thetrains of a series represent an element of a signal.

My invention comprises a system in which there may be receivedsimultaneously or independently, at a single station either by means ofa single receiving-conductor or several receiving-conductors, aplurality of messages or signals, each message'or signal beingrepresented by trains of waves of electroradiant energy succeeding eachother at a distinctive and uniform rate.

My invention comprises a system in which a plurality of messages orsignals maybe received, either simultaneously or independently, by meansof receiving-circuits, each of which selects a message or signal to theexclusion of all others in virtue of the rate of succession of thetrains of waves of electroradiant energy representing the message orsignal.

My invention comprises, further, a system in which at the receiver thetrains of waves of electroradiant energy representing messages orsignals control selective circuits in which are caused currents offrequencies equal to the frequencies of the trains of waves, and eachcircuit is so adjusted as to its electrical constants that it shallselect a current of a frequency equal to the rate of succession of thetrains of waves representing a message or signal.

My invention consists, further, in receiving simultaneously orindependently upon a single receiving-conductor a plurality of series oftrains of waves of electroradiant energy and subjecting a singlewave-responsive device to all the series of trains of waves, thewave-responsive device controlling the production of fluctuatingcurrents in as many local selective circuits as there are series oftrains of waves, each local circuit controlling a fluctuating current ofa frequency equal to the rate of succession of the trains of a singleseries, each series of trains of waves representing a message or signal.

My system comprises a plurality of stations each emitting trains ofwaves of electroradiant energy at a characteristic uniform rate and eachequipped with means for selecting the several messages or signals toseparate receivers or recorders, the trains of waves representing amessage or signal succeeding each other at a characteristic uniformrate. v

It has been customary heretofore in wireless signaling systems for thepurpose of securing selectivity to attune a circuit or circuits at thereceiving-station to the frequency of the transmitted electroradiantenergy waves. In my system, however, the selection or tuning hasreference more particularly to the rates of the trains of wavesrepresenting a message or signal. At'each spark at the spark-gap at thetransmitter there is emitted 5 from the radiating-circuit a train ofwaves of electroradiant energy, in some cases the number of waves pertrain reaching the number trains of waves of a certain station.

of two thousand, the frequency of said waves themselves being from inthe neighborhood of one hundred thousand per second to several millionsper second. The tuning or selecting has heretofore been accomplished byadjusting the constants of the receiving-circuit so as'to selectradiations of these enormously high frequencies. however, the selectionhas reference to the rate of succession of the trains of waves or, inother words, to the rate of succession of sparks at the spark-gap of thetransmitting apparatus.

In the primary of the transmitting-transformers I employ alternatingcurrents or reversed currents of a definite and uniform rate, so that atthe spark-terminals there are produced sparks at the same rate as therate of the current in the primary of the transformers. In other words,the rate of succession of the trains of waves of electroradiant energytransmitted is equal to the rate of the current in the primary of thetransmittingtransformer.

At the receiving-station instead of adjusting the circuits to thefrequency of the radiant energy itself there are produced in localcircuits fluctuating currents of a periodicity or frequency equal to therate of succes- 'sion of the trains of waves or, in other words,

equal to the rate of the sparks of the sparkgap at the transmitter andthe current in the primary of the transmitting-transformer. It is to beunderstood, however, that though my selectivity is obtained byadjustment of the constants of circuits with relation to the rate ofsuccession of the trains of waves I may in addition attune thereceiving-circuit to be selective of waves of electroradiant energy of acertain frequency, and thereby have double selectivity, or selectivityof two kinds.

In my system there may be a plurality of stations each emitting itstrains of waves at a characteristic and uniform rate, and eachreceiving-station of the system is supplied with as many selectivecircuits as there are remaining stations in the system, each circuitbeing adjusted as to its electrical constants to be selective offluctuating currents of a frequency equal to the rate of succession ofthe For example, station No. 1 may transmit trains of waves at the rateof two hundred per second, station No. 2 at the rate of three hundredper second, station No. 3 at the rate of three hundred and seventy-fivepersecond. Station No. 1 whenoperating as a receiver will have then twolocal circuits, one of which will select fluctuating currents of afrequency equal to three hundred per second, thereby selecting a messagecoming from station No. 2, and another circuit selective of fluctuatingcurrents of a frequency equal to three hundred and seventy-live persecond, which will select the message being transmitted from station No.3. Similarly when station No. 2 is operating as a receiver it will thenbe supplied with two In my system,

local circuits, one of which is selective of fluctuating currents of afrequency equal to two hundred per second, and therefore selecting themessage being transmitted from station No. 1, and another circuitadjusted to select fluctuating currents of a frequency of three hundredand seventy-five per second, and therefore selecting a message beingtransmitted from station No. 3. Likewise when station No. 3 is operatingas a receiver it has two local circuits, one of which is selective offluctuating currents ofafrequency of twohundred per second, andtherefore selective of the message being transmitted from station No. 1,and another circuit adjusted to select fluctuating currents of afrequency of three hundred per second, and therefore selective of themessage transmitted from station No.2. Though I have given but threestations in the example above, it is apparent how the number of stationsmay be increased simply by using different rates of succession for thetrains of waves at each station and adjusting local circuits at eachreceiver to be selective of fluctuating currents of like frequencies.

At my receiving-station I prefer to employ a single wave-responsivedevice, preferably of the self-restoring type, which is subjected to thetrains of waves arriving from the stations which may be simultaneouslytransmitting. In local circuits shunted around such wave-responsivedevice are means for rendering such circuits selective of fluctuatingcurrents corresponding with the different trains of waves received, andthere is common to all the local circuits a source of energy giving riseto such fluctuating currents under the control of the singlewave-responsive device. At the transmitting-station an alternatingcurrent or a commutated direct current is employed in the primary of thetransmitting-transformer,thereby setting the rateof'succession of thetrains of waves emitted by such transmitter.

For a detailed description of my invention reference is to be had to theaccompanying drawings, in which- Figure 1 represents in diagram thecircuits at a receiving-station whereby two simultaneously-receivedmessages may be separated and read or interpreted independently of eachother. Fig. 2 represents in diagram the circuits at a receiving-stationcapable of recording independently four simultaneously-receivedmessages. Fig. 3 represents in diagram a receiving-station employing twoaerial conductors and a local circuit in conjunction with each aerialconductor, such 10- cal circuits, however, being selective offluctuating currents of different frequencies. Fig. -i is a view indiagram of the circuits at a transmitting-station where trains of Wavesmay be emitted at three different rates. Fig. 5 is a view in diagram ofthe circuits at a transmitter whereby trains of waves of different ratesof succession maybe alternately :impresseduponthe natural media by asin-;

gle oscillatory transformer and a single key. Fig. 6 is an enlarged viewof one of the commutators employed at the transmitters. Fig. 7 is a sideviewof the commutator shown in Fig. 6.

In Fig. 1, A represents the usual aerial conductor of a wirelesssignaling system, between which and the earth-plate E is connected thewave-responsive device 0 and which is preferably of any of theself-restoring typesfor example, an electrolytic device, carbon device,or the carbon and metal devices. In shunt relation with thewaveresponsive device 0 are two local circuits, one embracing thecondenser 1 and the telephonereceiver 2,the other embracing theinductance 4c and the telephone-receiver 5. Common to both thesecircuits are the choke-coils ff and the batteryor source of energy 3. Bythis arrangement of circuits it is possible to receive simultaneouslytwo distinct messages upon the aerial conductor A and separate them totwo distinct and separte translating devices, such astelephone-receivers. For example, one of the messages being received maybe represented by trains of waves following each other at the rate offour hundred per second, while the other messages may be represented bytrains of waves succeeding each other at the rate of one hundred andfifty per second. Under these circumstances the waveresponsive device 0,which it is to be remembered is preferably self-restoring, alters itscondition under the influence of both series of trains of waves and setsup, therefore, in the portions of the local circuits comprisingchoke-coils ff and the battery 8 two distinct currents of differentfrequencies. One of these currents fluctuates at the rate of fourhundred per second, because the wave-responsive device 0 alters itscondition four hundred times per second under the influence of the wavesrepresenting one message, and also a current at the rate of one hundredand fifty fluctuations per second, due to the one hundred and fiftychanges in the condition of the wave-responsive device c in a secondunder theinfluence of the trains of waves representing the othermessage.

In the circuit embracing condenser l and the telephone-receiver 2 willbe selected currents of the higher frequenciesnamely, four hundred persecond-while in the circuit embracing inductance 4 and thetelephoned-cceiver 5 will be selected currents of lower frequencies orat the rate of one hundred and fifty per second.

It is a well-known fact that low-frequency currents can be separated orselected from high-frequency currents by this arrangement, because thecondenser permits more easily the passage of high-frequency currents andexcludes the low-frequency, Whereas the inductance excludes thehigh-frequency and permits more readily the passage of low-frequencycurrents. The result is that in telephone-receiver 2 will be receivedthe message represented by trains of waves succeeding each other at therate of four hundred per second, while in the telephone-receiver 5 willbe received the message represented by the trains of waves succeedingeach other at the rate of one hundred and fifty per second. It isnecessary, however, when it is desired to distinguish and separate morethan two simultaneously-received messages to resort to the systemdescribed in Fig. 2. Here, again, A represents the usual aerialconductor of a wireless signaling system, between which and the earthconnection E is the waveresponsive device 0, preferably of theselfrestoring type, as described above. Chokecoils ffand the source ofenergy or battery 9 are arranged as in the case of Fig. 1. Here areagain shown four local circuits, the first embracing the condenser 6,inductance 7, and telephone-receiver 8; the second, condenser 10,inductance 11, and telephone-receiver 12; the third, condenser 13,inductance 14C, and telephone-receiver 15; the fourth, condenser 16,inductance 17, and telephone-receiver 18. In these circuits a condenserand inductance are employed conjointly and operate, as is well known inthe art of fluctuating currents, to respond more sharply to afluctuating current of certain frequency to the almost enone frequencyto the exclusion of others,

circuit 12 will respond to anotherfrequency, and the circuits oftelephone-receivers 15 and 18 will respond to still differentfrequencies of currents. The action of the several series of trains ofwaves upon the wave-responsive device 0 in causing it to produce in thelocal circuits fluctuating currents of different frequencies is the sameas that described in connection with Fig. 1. circuits shown in Fig. 2,however, four messages may be simultaneously received and independentlyrecorded to the tuning of local circuits by combined capacity andinductance. 2 produces sharper selectivity than in the case of Fig. 1,which may be said to select roughly rather than sharply.

In Fig. 3 I have shown two aerial conductors A A in place of a singleone, and in conjunction with each is a wave-responsive device o. In thelocal circuit of each waveresponsive device is atelephone-receiver 2 andcondenser 1, therefore corresponding with the circuit includingcondenser 1 and telephonereceiver 2 in Fig. 1. In shunt to the otherwave-responsive device is the circuit including inductance 4 andtelephone-receiver 5, as shown in Fig. 1, by the circuit including inductanee 4 and telephone-receivers In this case the wave-responsivedevices are separate, and though both aerial conductors re- By thearrangement of The arrangement shown in Fig..

cate with source of direct current 20.

greater number of segments.

ceive energy representing both messages, yet only the messagerepresented by the trains of waves succeeding each other at high rateare received by telephone-receiver 2, and the message represented bytrains of waves succeeding each other at low rate is recorded intelephone-receiver 5.

In Fig. 4 is shown an aerial conductor A, which is common to threeoscillators. Conductor A, spark-gap 50, condenser 51, and earthconnection E represent one oscillating circuit. Conductor A, spark-gap46, condenser 47, and earth connection E represent another oscillatingcircuit, and the conductor A, spark-gap 42, condenser 43, and earthconnection E represent the third oscillating circuit. The spark-gap 50is shunted by the secondary of the transformer 49, in whose primary isthe controlling or operators key 48 in series with the brushes 34 and35, which bear upon commutator L, comprising two metallic portions 22and 23, interspaced, as shown, and separated from each other byinsulating material 53'. Brushes 28 and 29 bear continuously upon 22 and23, respectively, and are in communication with the source of energy orbattery 20. 21 is an electric or other motor which is continuouslyrotating and driving the shaft 52, upon which are} mounted severalcommutators. As is well understood in the art, the rotation ofcommutatorsLcauses commutation of the direct current from source ofenergy into reversed currents, which pass through brushes 34 and 35through the primary of the transformer 49. In shunt to the spark-gap 46is the secondary of the transformer 45, in whose primary are operatorskey 44 and the brushes 36 and 37 in series. These brushes 36 37 bearupon commutator M, composed of the interspaced parts 24 25, separated byinsulating material 53. The brushes 30 31 bear upon members 24 25,respectively, and communi- The result of the rotation of the commutatorM by the motor 21 causes reversed current to flow through the primary ofthe transformer when the key 44 is depressed; but the rate of suchcurrent is higher than that of the current flowing through the primaryof transformer 49, because commutator M has a In shunt to the spark-gap42 is a secondary of the transformer 41, in whose primary is thecontrolling or operators key 40 in series with the brushes 38 39. Thesebrushes bear alternately, as in the former case, upon members 26 and 27on commutator N, these portions 26 and 27 being interspaced. butseparated by insulating material 53. Upon these members 26 27 bearcontinuously the brushes 32 and 33, respectively, which are incommunication with source of direct current 20. CommutatorN is driven bythe same motor 21and causes a commutation of the direct current, whichthen flows through brushes 38 39 through the primary of transformer 41when key 40 is depressed. The rate of the currents through the primaryof the transformer 41 is still greater than that of the currents throughthe transformer 45. This is due to the greater number of segments incommutator N than in commutator M. It is seen that the motor 21 drivescommutators L M N simultaneously, but that due to their differentnumbers of segments they produce reversed currents of as many differentfrequencies. The condensers 43 47 51 are for the purpose of preventinginterchange of energy between the secondaries of the transformers 41,45, and 49. These condensers are of relatively small capacity, andtherefore operate as impeding devices to the comparatively low frequencycurrents in these secondaries, though such condensers do not interferewith the extremely high oscillations in the radiating circuits.

Although in my system each transmitter need emit trains of waves at asingle rate only, yet by the arrangement just described at a singletransmitting-station three difiercut rates are possible. By insertingbetween the spark-gap and the aerial conductor A an inductance Landbetween the spark-gap 46 and the aerial conductor A an inductance L ofdifferent magnitude and between the spark-gap 42 and the aerialconductor A an inductance L -of a still different value it is possibleto simultaneously transmit from the aerial conductor A a plurality ofseries of trains of waves at different rates and also to give to thewaves of each series different periods. By depressing key 40, forexample, trains of waves are emitted from the aerial conductor at arelatively high rate. By depressing key 44 trains of Waves are emittedat a relatively lower rate, and by depressing key 48 trains of waves areemitted at a still lower rate. By this arrangement of the transmittingapparatus it is possible to send a message which may be read at acertain receiving-station only, while the receiving-station is suppliedin its local circuit, as above described, with means for selectingfluctuating currents of a rate equal to that of the rate of successionof the trains of waves transmitted from a certain transmitting-station.For example, by depressing key 40 at a certain station a message may besent to a certain other station, which receiving-station in the entire 4system is the only one having a local circuit selective of fluctuatingcurrents of a rate equal to the rate of succession of the trains ofwaves emitted by oscillator controlled by key 40, such rate beingdependent upon the number of segments in commutator N.

In Fig. 5 is shown a radiating aerial conductor, in series with whichand the earth connection E is the spark-gap 59. In shunt tothe-spark-gap 59 is the secondary of the transformer 58, in the circuitof whose-primary is the key 57. 21 represents an electric or othermotor, which rotates continuously, driving shaft 52 and the commutatorsL, M, and N. The brushes bearing upon these c0mmutators are numberedsimilarly to those in connection with Fig. 4, and the source of energy20 is of the direct-current type in connection with the brushes bearingupon all the commutators. In series with the brush 38 is switch 54, inseries with brush 36 is switch 55, and in series with brush 34 is switch56. By closing any one of these switches 54, 55, or 56 and depressingthe key 57, a reversed current will be sent through the primary of thetransformer 58, and the rate of this current is dependent upon thenumber of segments in the commutator employed and also upon the rate ofrotation of the shaft For example, if the switch 54 is closed and key 57is depressed a relatively high frequency reversed current will be passedthrough the primary of the transformer 58. If, however, switch 55 isclosed and key 57 is depressed, a reversed current of lower frequencywill be passed through the primary of the transformer 53 and likewise ifswitch 56 were closed and the key 57 depressed a reversed current ofstill lower frequency would be passed through the primary of thetransformer 58. It is thus seen that with a singleoscillatorytransformer and a single operators key there maybe impressedat will upon the natural media different series of trains of waves, theseries differing from each other in rate of succession of the trains ofwaves.

By the arrangement of circuits shown in Fig. 5 it is possible,therefore, to transmit trains of waves at different rates for thepurpose of influencing a certain receiver, as explained in connectionwith Fig. 4.

Fig. 6 is an enlarged view of a commutatoras,for example M-which hasinterspaced metallic portions 24 and 25, which are separated from eachother byinsulating material 53.

In Fig. 7 is shown a side view of this commutator M, which has a centralmetallic portion which secures the commutator to the shaft 52, whichpasses through the central opening therein shown. Surrounding thisportion is insulating material 53, and upon this insulating material ismounted the metallic portions 24 and 25, of which 25 is seen in edgeView. Of the two brushes 30 and 31, 31 only appears in this view, and itmay be said that the angular relations of these two brushes 30 31 isimmaterial. The brushes 36 37 are shown displaced, however, as to theirangular positions, and such is essential, as is well known in connectionwith com mutators of this type. The bearing points of the brushes 36 37should be an angular distance apart equal to the angular distancebetween the centers of alternate segments of the commutator.

Though I have shown but one receivingstation with different methods ofarrangement of circuits at such station and though I have shown but twosingle transmitting apparatus, it is to be understood that in my systemare a plurality of stations each equipped with devices herein shown anddescribed. It is to be further understood that though I selectprincipally by tuning the receiving-circuits to the rate of successionof the trains of waves 1 may also attune the aerial receiving-circuit orcircuits arranged in inductive or conductive relation therewith to therate of the waves themselves, thus securing, in effect, a double tuning.For example, at a certain station the rate of succession of the trainsof waves may be three hundred .per second, while the rate of the wavesthemselves may be five hundred thousand per second. At thereceivingstation the circuit including or controlling the wave-responsive device would be attuned to a rate of five hundred thousand persecond, while at the same time the local circuit controlled by saidwave-responsive device to select the particular message would besolective of fluctuating currents of a rate of three hundred per second.

It is to be understood that the arrangement of the wave-responsivedevice need not be confined to the series arrangements herein shown, butthat it may be arranged in a circuit. inductively connected with theaerial circuit or it may be connected in shunt to thefrequency-determiningelement of a resonant receiving-circuit, as is nowwell understood in the art. l urthermore, it is to be understood thatinstead of a single wave-responsive device in conjunction with a singleaerial conductor a plurality of wave-responsive devices may be usedeither in series relation, parallel relation, or series-parallelrelation. It is to be further understood that in conjunction with asingle aerial conductor may be employed several branch circuits, suchcircuits when taken in conjunction with the aerial conductor formingcircuits selective of different rates of transmitted waves.

This application is a division of application filed September 13, 1902,and bearing Serial No. 123,237.

I do not claim herein the broad intention of selection by means ingeneral and of any kind, but reserve the same for another application.Herein I claim as the selecting means a circuit in virtue of whoseelectrical properties a predetermined message or signal is received tothe exclusion of others.

WVhat I claim is- 1. In a wireless signaling system, a waveresponsivedevice, and a plurality of selective circuits controlled thereby.

2. In a wireless signaling system, a waveresponsive device, and aplurality of parallel selective circuits controlled thereby.

3. In a wireless signaling system, a waveresponsive device, and aplurality of circuits controlled thereby, each selective of apredetermined message. i y

4. In a wireless signaling system, a waveresponsive device, and aplurality of parallel circuits controlled thereby, each selective of apredetermined message.

5. In a wireless signaling system, a waveresponsive device, and aplurality of circuits controlled thereby, each attuned to a ratecorresponding with the rate of succession of the wave-trainsrepresentinga predetermined message.

6. In a wireless signaling system, a self-restoring wave-responsivedevice, and a plurality of selective circuits controlled thereby.

7. In a wireless signaling system, a self-restoring wave-responsivedevice, and a plurality of parallel selective circuits controlledthereby.

8. In a wireless signaling system, a self-restoring wave-responsivedevice, and a plurality of circuits controlled thereby, each selectiveof a predetermined message.

9. In a Wirelesssignaling system, a self-restoring wave-responsivedevice, and a plurality of circuits controlled thereby, each select iveof a current fluctuating at a predetermined rate.

10. In a Wireless signaling system, a self-restoring wave-responsivedevice, and a plurality of parallel circuits controlled thereby, eachselective of a separate message.

11. In a wireless signaling system, a self-restoring wave-responsivedevice, and a plurality of parallel circuits controlled thereby, eachselective of a current fluctuating at a rate characteristic of apredetermined message.

12. In a wireless signaling system, a waveresponsive device, and aplurality of circuits controlled thereby, each circuit so adjusted as toits electrical constants as to be selective of a current fluctuating ata predetermined rate.

13. In a wireless signaling system, a Waveresponsive device, and aplurality of parallel circuits controlled thereby, each so adjusted asto its electrical constants as to be selective of a current fluctuatingat a predetermined rate.

14. In a wireless signaling system, aself-restoring wave-responsivedevice and a plurality of circuits controlled thereby, each circuit soadjusted as to its electrical constants as to be selective of a currentfluctuating at a predetermined rate.

15. In a Wireless signaling system, a self-restoring wave-responsivedevice, and a plurality of parallel circuits controlled thereby, each soadjusted as to its electrical constants as to be selective of a currentfluctuating at a predetermined rate.

16. In a wireless signaling system, a self-restoring Wave-responsivedevice, and a plurality of circuits controlled thereby, each so adjustedas to its electrical constants as to be selective of a currentfluctuating at a rate characteristic of a predetermined message.

17. In a Wireless signaling system, a waveresponsive device, and acircuit controlled thereby, said circuit including capacity andinductance s0 related as to render said circuit selective of a currentfluctuatingat a predetermined rate. r

18. In a Wireless signaling system, a waveresponsive device, and acircuit controlled thereby, said circuit including capacity andinductance so related as to render said circuit selective of a currentfluctuating at a ductance and capacity so related as to render thecircuit selective of a current fluctuating at a predetermined rate.

20. In a Wireless signaling system, a Waveresponsive device, a pluralityof parallel circuits controlled thereby, a capacity and inductance ineach circuit and so related as to render each circuit selective of -acurrent fluctuating at a rate characteristic of a predetermined message.

21. In a wireless signaling system, a receiving-circuit, and a pluralityof circuits controlled thereby, each circuit being selective of acurrent fluctuating at a rate characteristic of a predetermined message.

22. In a wireless signaling system, a receiving-circuit, influenced byaseries of wavetrains, each series representing a separate message, andaplurality of circuits controlled by said receiving-circuit, eachselective of a current fluctuating at a rate equal to the rate ofsuccession of the trains in a certain series.

23. In a wireless signaling system, areceiving-conductor, awave-responsive device influenced by a plurality of series ofwavetrains, each series consisting of trains succeeding each other atcharacteristic rate, and a plurality of circuits controlled by saidwaveresponsive device, each selective of a message represented by aseries of wave-trains succeeding each other at characteristic rate.

24:. In a wireless signaling system, areceiving-conductor, awave-responsive device influenced by a plurality of series ofWavetrains, the trains of each series succeeding each other atcharacteristic rate, and a plurality of parallel circuits controlled bysaid wave-responsive device, each selective of a message represented bya series of Wavetrains succeeding each other'at characteristic rate.

25. In a Wireless signaling system, a receiving-circuit attuned to therate of the transmitted electroradiant-energy Waves, a Wave responsivedevice influenced by energy received in said circuit, and a localcircuit controlled by said Wave-responsive device and selective of amessage represented by Wavetrains succeeding each other at predeterminedrate.

26. In a wireless signaling system, a transmitter comprising means fortransmitting wave-trains at a predetermined, uniform rate, a receivercomprising a wave-responsivedevice, and a local circuit controlledthereby and selective of a message represented by the wave-trainssucceeding each other at predetermined rate.

27. In a Wireless signaling system, a transtuned to a rate equal to therate of succession of the transmitted wave-trains.

29. In awireless signaling system, a transmitter comprising means foremitting wavetrains at a predetermined uniform rate, and for giving tothe waves of a train a predetermined periodicity, areceiving-circuitattuned to the periodicity of the energy-waves,awaveresponsive device included in said circuit,

and a local circuit controlled by said waveresponsive device andselective of a message represented by the Wave-trains succeeding eachother at the predetermined rate.

30. In a Wireless signaling system, a transmitter comprising means foremitting wavetrains at a predetermined uniform rate, and for giving tothe waves of a train a predetermined periodicity, areceiving-circuitattuned to the periodicity of the energy-waves, awave-responsive device included in said circuit, and a local circuit,controlled thereby and selective of a current fluctuating at a ratecorresponding with the predetermined rate of succession of thewavetrains.

31. In a wireless signaling system, a transmitter comprising means foremitting wavetrains at a predetermined uniform rate, and for giving thewaves of a train a predetermined periodicity, a receiving-circuitattuned to the periodicity of the energy-Waves, a wave-responsive deviceincluded in said circuit, and a local circuit, controlled thereby andattuned to a rate equal to the rate of succession of the transmittedwave-trains.

32. In a wireless signaling system, a plurality of transmitters eachemitting wavetrains at characteristic and uniform rate, areceiving-conductor, a wave-responsive device influenced by energiesreceived by said conductor, and a plurality of circuits controlled bysaid wave-responsive device, each selective of a current fluctuating ata rate equal to the rate of succession of the wavetrains emitted by acertain transmitter.

33. In a Wireless signaling system, a plurality of transmitters, eachemitting wavetrains at characteristic rate, the Waves of the trainshaving definite periodicity, areceivingcircuit attuned to theperiodicity of the waves of the trains, a wave-responsive deviceinfluenced by the energies received by said circuit, and a plurality ofcircuits controlled by said wave-responsive device, each selective of acurrent fluctuating at a rate equal to the rate of succession of thewave-trains emitted by a certain transmitter.

34. In a wireless signaling system, a receiving-conductor, awave-responsive device influenced by energy received by said conductor,and a local selective circuit controlled by said wave-responsive device.

35. In a wireless signaling system, a selfrestoring Wave-responsivedevice, and a local selective circuit controlled thereby.

36. In a wireless signaling system, a waveresponsive device, and acircuit controlled thereby selective of a current fluctuating at apredetermined rate.

37. In a wireless signaling system, a selfrestoring wave-responsivedevice, and a local circuit controlled thereby selective of a currentfluctuating at a predetermined rate.

38. In a wireless signaling system, a circuit selective of a currentfluctuating at a rate equal to the rate of succession of transmittedwave-trains.

39. In the receiving-circuit of a' wireless signaling system, aself-restoring Wave-responsive device, and a circuit controlled therebyselective of a current fluctuating at a rate equal to the rate ofsuccession of the transmitted Wave-trains.

40. In the receiving-circuit of a Wireless signaling system, a circuitattuned to the rate of succession of the transmitted wavetrains.

41. In the receiving-circuit of a Wireless signaling system, a localcircuit selective of a current fluctuating at a rate equal to the rateof succession of the transmitted wavetrains.

42. In the receiver of a wireless signaling system, a local circuitattuned to the rate of succession of the transmitted Wave-trains.

43. In the receiver of a Wireless signaling system, a self-restoringWave-responsive device, a local circuit controlled thereby and attunedto the rate of succession of the transmitted wave-trains.

HARRY SI-IOEMAKER.

Witnesses:

FREDK. W. MIDGLEY, JAMES M. SAWYER.

